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David Knecht wrote:

> Is the excitation spot size for a laser scanning confocal microscope
> the same as that of an epifluorescence widefield microscope (same
> objective, etc.)?  Put another way, if I removed the PMT pinhole,
> would I get an image comparable to a widefield image?  Thanks- Dave

If I understand you correctly, the answer is no.  For a widefield
microscope, the entire field of view is illuminated at one time.  For a
confocal microscope (under ideal circumstances, at least), the area of
excitation is a diffraction-limited spot--i.e. it's sub-micron,
depending on wavelength and how you define the edge.

Martin
--
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